吡喹酮和硝硫氰醚对日本血吸虫体内5-HT含量的影响

本文研究了吡喹酮和硝硫氰醚与日本血吸虫拟似神经递质 5-羟色胺间的关系。以吡喹酮 ( 5× 1 0 - 7mol/ L和 5× 1 0 - 8mol/ L )、硝硫氰醚 ( 1 0 - 4mol/ L和 1 0 - 5mol/ L )分别培养日本血吸虫成虫 4h和 8h ,反相离子对高效液相法测定其体内 5-HT的含量变化。结果显示 :吡喹酮和硝硫氰醚对日本血吸虫体内 5-HT等含量的影响与对照相比均无显著性差异。表明二者抗虫作用似不通过影响虫体 5-HT的生物合成和降解。     

甘肃滩羊血红蛋白(Hb)及红细胞蛋白质(Ep)多态性的研究

运用聚丙烯酰胺凝胶电泳技术(PAGE)对甘肃滩羊产区皋兰、景泰及靖远3县285只滩羊的血红蛋白(Hb)基因座、红细胞蛋白质-1(Ep-1)和红细胞蛋白质-2(Ep-2)基因座多态性进行了检测,结果发现甘肃滩羊Hb基因座存在3种基因型HbAA、HbAB、HbBB,它们受HbA和HbB两个共显性等位基因控制,其中HbB和HbBB在3个群体中均占优势;本研究未在Ep-1和Ep-2基因座上检测到多态性,它们均呈现单态。     

A review of feline serum protein electrophoresis

A review of the current literature available on feline serum proteins is presented. Early studies concentrated on comparative aspects of species variations in the electrophoretic pattern. The feline electrophoretogram was divided into five basic regions: albumin, alpha-1, alpha-2, beta and gamma. Different subdivisions of these areas were recognized depending on the support medium used. Current papers have compared the relative migration distances of each globulin peak to the migration of albumin. This "Rf" value enables reliable peak identification. To date, no data exists identifying the individual proteins responsible for the peaks in the alpha and beta regions. The only feline globulin to be studied is haptolobin; however its precise location on the electrophoretic strip was not identified.     

Dynamics ofRhizoctonia solani (black scurf) in successive potato crops

The position of plants withRhizoctonia solani sclerotia (black scurf) on progeny tubers was mapped for an experimental field at Haren where potatoes were grown continuously and in rotation with other crops for five successive years, and for another field at Borgercompagnie with a 12 frequency of potatoes during three potato crops. Initially, the distribution of plants with black scurf on both fields was rather dense and homogeneous. In the following years the distribution became heterogeneous and patchy. The local decline ofR. solani AG 3 (the common potato pathogen) in Haren was apparently caused by an unknown factor selectively suppressingR. solani AG 3, while simultaneouslyR. solani AG 5 increased in mass. This AG 5 type proved to be an inferior competitor of AG 3 on the potato plant in a laboratory experiment. The specificR. solani antagonistVerticillium biguttatum did not play a role. A similar factor could have reduced the formation of black scurf in the experimental field at Borgercompagnie, whereV. biguttatum was also too infrequent to account for the decline.R. solani AG 5 was not present here and could not indicate the presence of a selective factor against AG 3.     

Comparison of the effects of salicylic acid and ethephon with virus-induced hypersensitivity and acquired resistance in tobacco

The induction of a hypersensitive reaction in Samsun NN tobacco by tobacco mosaic virus (TMV) at 20°C leads to the development of both localized and systemic acquired resistance, and is associated with the appearance of pathogenesis-related proteins (PR's) and large increases in peroxidase activity and ethylene production. Salicylic acid (SA) induced a similar resistance in treated plant parts and occasionally also in untreated upper leaves of plants of which three lower leaves had been injected. SA also induced the same four PR's, but these were confined to the treated leaves. Thus, the connection between the presence of PR's and the reduction of TMV multiplication and spread may not be direct.In contrast to TMV, SA did not stimulate ethylene production and hardly increased peroxidase activity. Induction of acquired resistance and PR's by SA developed equally well at 20°C and at 32°C. However, pricking leaves with needles moistened with the ethylene-releasing compound ethephon mimicked TMV infection in inducing acquired resistance and PR's in both treated and untreated leaves at 20°C, but not at 32°C. Ethephon increased peroxidase activity at both temperatures, but only at 20°C dit it induce changes in both the anodic and the cathodic isoenzymes that were similar to those induced as a result of TMV infection. SA induced PR's and reduced TMV multiplication in Samsun tobacco, and inhibited virus spread in Samsun NN at 32°C.These observation indicate that neither the induction of PR's, nor the development of acquired resistance is temperature-sensitive. On the other hand, the effects of ethephon are temperature-sensitive in the same way as the hypersensitive response to TMV. It can thus be hypothesized that ethylene, produced naturally during the hypersensitive reaction of tobacco to TMV, leads to the temperature-sensitive synthesis or release of a presumably benzoic acid-type compound that functions as the natural inducer of PR's and acquired resistance. Although vanillic acid has been shown to accumulate in hypersensitively reacting tobacco leaves, it produced none of the effects of SA, and thus cannot be the natural inducer.Samenvatting Inductie van een overgevoeligheidsreactie in Samsun NN-tabak door tabaksmozaïekvirus (TMV) bij 20°C leidt tot de ontwikkeling van een verworven resistentie die zowel lokaal als systemisch werkzaam is, en gaat samen met het verschijnen van pathogenesis-related proteins (PR's) en sterke toename in de activitieit van peroxidase en de produktie van ethyleen. Salicylzuur (SA) induceerde een vergelijkbare resistentie in behandelde plantedelen en af en toe ook in niet behandelde bovenbladeren van planten waarvan drie onderbladeren waren ingespoten. SA induceerde ook dezelfde vier PR's, maar deze waren beperkt tot de behandelde bladeren. Er bestaat dus geen directe samenhang tussen de aanwezigheid van PR's en de remming van de vermeerdering en uitbreiding van TMV in de plant.In tegenstelling tot TMV stimuleerde SA de ethyleenproduktie niet en verhoogde het de peroxidaseactiviteit nauwelijks. Inductie van verworven resistentie en PR's door SA trad even goed op bij 32°C als bij 20°C. Net als infectie met TMV leidde aanprikken van bladeren met naalden die gedoopt waren in een oplossing van ethefon — waaruit in het blad ethyleen vrijkomt — echter tot inductie van verworven resistentie en PR's in zowel behandelde als onbehandelde bladeren bij 20°C, maar niet bij 32°C. Ethefon verhoogde de peroxidaseactiviteit bij beide temperaturen, maar alleen bij 20°C induceerde het veranderingen in zowel de anodische als de kathodische isoënzymen die vergelijkbaar waren met die welke geïnduceerd werden als gevolg van infectie met TMV. SA induceerde PR's en verminderde de vermenigvuldiging van TMV in Samsun tabak, en remde de uitbreiding van het virus in Samsun NN bij 32°C.Deze waarnemingen tonen dat noch de inductie van PR's, noch de ontwikkeling van verworven resistentie een temperatuurgevoelig proces is. Daarentegen zijn de effecten van ethefon op dezelfde wijze temperatuurgevoelig als de overgevoeligheidsreactie op TMV. Men kan daarom veronderstellen dat ethyleen, dat op natuurlijke wijze geproduceerd wordt tijdens de overgevoeligheidsreactie van tabak op TMV, aanleiding geeft tot een temperatuurgevoelig proces, namelijk de synthese of het vrijkomen van een verbinding, vermoedelijk een benzoëzuurderivaat, dat fungeert als de natuurlijke inductor van PR's en verworven resistentie. Hoewel is aangetoond dat vanillinezuur zich ophoopt in overgevoelig reagerende tabaksbladeren, veroorzaakte deze verbinding geen enkel van de effecten van SA. Vanillinezuur kan dus niet de natuurlijke inductor zijn.     

South-Western blot mapping方法的建立及其应用于锥虫细胞核中DNA结合蛋白的观察

South-Westerm blot mapping是一种结合Western blotting和Southern blotting某些特点的方法.本文介绍用其成功地观察到锥虫核蛋白中DNA结合蛋白的情况,并对一个分子量在40000左右、于较严谨条件下与DNA结合的核蛋白进行了特性鉴定.该蛋白等量地存在于锥虫的前循环期和血液期,对双链DNA有较大的亲和力,并能与酵母菌复制起始片段结合.本文还介绍了锥虫细胞核的提取技术和核蛋白的制备技术.     

The effect of some Frescon analogs on the aquatic snail,Lymnaea stagnalis: II. Correlation of neurotoxicity to Molluscicidal effectiveness

Although the molluscicide Frescon is a strong neurotoxin to the Lymnaea stagnalis central nervous system in vitro, it is probable that the exposure of the whole animal to this molluscicide fails to result in central nervous system abnormalities: Frescon does not appear to reach the brain in sufficient quantity to disrupt its normal activity. However, only those Frescon analogs found to be neurotoxic were molluscicidal, suggesting some related mode, if not site, of action. Frescon and its analogs may act by affecting excitable tissues other than the nervous system (e.g., the snail musculature) by altering certain functional and/or structural membrane properties.     

节能日光温室光照强度的分布及其变化

在充分考虑了温室结构和植株生长影响的基础上,对日光温室光照强度的变化规律进行了研究,得到的主要结论如下:冠层上部辐射强度的南北差异比东西差异大;冠层下部光照条件东西差异明显,南北差异不大。总体上讲,辐射强度上下差异比南北差异明显。     

西北干旱灾害及其气候趋势研究

利用西北五省1950～2000年降水、温度和农作物旱灾面积资料,用降水的Z指标法,农作物受旱成灾率确定了西北干旱指标和旱灾等级,分析了西北旱灾特征及气候变化趋势。表明西北农业旱灾以70、90年代最严重,而且呈增加趋势,气温在升高,降水在减少。根据预测21世纪前十年西北干旱有所减轻。     

Detection,cloning and expression of bone morphogenetic protein-1 from human osteosarcoma cell lines

AIM:To manufacture recombinant protein of the highly conserved domain in human bone morphogenetic protein-1(BMP-1) using gene engineering methods as antigen for making wide spectrum antibody to BMP-1.METHODS:We analyzed the gene sequences and protein structures of BMP-1 and its related proteins, and chose a highly conserved fragment as target gene. Total RNA was prepared from human osteosarcoma cell line Saos-2, then the target gene was amplified with RT-PCR. The PCR product was cloned into prokaryotic expression vector pMAL c2 to get recombinant vector BMP-1(322-588aa)-pMAL c2. After transforming the recombinant plasmid into DH5-alpha and screening, several prositive clones were got for sequencing. Finally the transformed cells was induced with IPTG to get fusion protein.RESULTS:The BMP-1 gene fragment was successfully cloned into vector pMAL c2, and was able to express efficiently with IPTG inducement. The amount of expressed fusion protein is about 66%-72% in total volume of bacterial proteins.CONCLUSIONS:The recombinant protein contains several key domains(2 CUB domains and 1 EGF domain), which are shared by BMP-1 and its related proteins. Specific wide spectrum antibody to human BMP-1 and its related proteins may be generated with this recombinant protein antigen.